1. Field of Invention
The present invention relates to a kimchi refrigerator, and more particularly, to a kimchi refrigerator including an inner casing which is configured to maximally suppress the temperature increase in the kimchi refrigerator against an external high-temperature environment.
2. Description of the Prior Art
A perspective view of a chest-type kimchi refrigerator is shown in FIG. 1. As shown in this figure, the chest-type kimchi refrigerator (hereinafter, referred to as a kimchi refrigerator) comprises a main body 10 with an open upper face and a storage space 16, and a door 20 for allowing the open upper face of the main body 10 to be opened and closed.
Further, the main body 10 comprises an outer casing 12 made of a metal plate to define an external appearance of the refrigerator and an inner casing 14 installed in the outer casing 12 to define the upwardly opened storage space 16. An insulating layer is formed between the outer casing 12 and the inner casing 14. The inner casing 14 is made of a material with high thermal conductivity, e.g. aluminum. In addition, since the door 20 is connected to the main body 10 by hinges 22, the door is pivoted to open and close the storage space 16 of the main body 10.
As can be seen from FIG. 2, the kimchi refrigerator is mounted with a heat exchanger for generating cold air to keep foodstuffs, e.g. kimchi, stored in the inner casing 14 in a refrigerating state, and a heater necessary to ripen the kimchi. Further, in consideration of the convection of air in the storage space 16 of the kimchi refrigerator, an evaporator is installed at an upper portion on an outer periphery of the inner casing 14 and a heater is installed at a lower portion on the outer periphery of the inner casing 14. In a direct cooling type refrigerator, the evaporator is generally composed of refrigerant tubes 18 which repeatedly surround the upper portion on the outer periphery of the inner casing 14. In addition, the heater 19 is installed at the lower portion on the outer periphery of the inner casing 14. The refrigerant tubes 18 and the heater 19 provide cold air necessary to store kimchi in a refrigerating state and heat necessary to ripen kimchi, respectively.
In order to most efficiently perform the heat exchange between the refrigerant tubes 18 and the heater 19, the conventional inner casing 14 has been made of a single material with high thermal conductivity, e.g. aluminum. The refrigerant tubes 18 and the heater 19 are attached to an outer surface of the inner casing 14 by using aluminum tapes Ta and Tb or the like having high thermal conductivity.
In the conventional kimchi refrigerator so configured, the external air with relatively higher temperature is introduced in the refrigerator when the door 20 is opened to put foodstuffs into or out of the storage space. If the high temperature external air is introduced into the storage space 16, an upper portion of the inner casing 14 is exposed to a high-temperature environment. Thus, the temperature of the upper portion of the inner casing 14 made of a material with high thermal conductivity is easily increased, and the temperature of the lower portion of the inner casing 14 formed of the same material is also rapidly increased. This means that the temperature in the inner storage space defined by the inner casing 14 is substantially rapidly increased.
The conventional kimchi refrigerator so configured has the following problems. That is, the internal temperature of the refrigerator is substantially easily raised as the door is opened and closed. Thus, the freshness of foodstuffs stored in the refrigerator can be substantially reduced due to the above phenomenon and electric power consumption can also be increased.